The present invention relates to oral dosage forms with controlled total-release of an active substance, wherein the same active substance is present in the form of at least two different salts which are present in the dosage form in a solid aggregation state and which have a different in-vitro release of this active substance.
Administration of an active substance in the form of preparations, from which this active substance is released in a controlled manner, is advantageous for many therapies. For example, the controlled release of an active substance with a relatively short half-life will prolong its availability in the body. Moreover, uniform blood levels can be adjusted in this manner; any undesirable accompanying symptoms may, optionally, be minimised; and observance of dosage specifications can be improved.
Conventionally, the controlled release of an active substance from oral dosage forms can be achieved only through relatively expensive formulation procedures, such as coating the oral dosage forms containing active substances with a retarding film coating or embedding the active substances in a retarding matrix. If a different release of partial quantities of an active substance is required in order to control the overall release profile, the same active substance or the same active-substance salt may be processed separately to provide different formulations, which may then be combined, for example, as a retarded and a non-retarded form of one dosage form.